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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Environmental Impact of E-Commerce Logistics : When is Home Delivery More Efficient than Collection-Delivery Points? / Miljöpåverkan av e-handelslogistik : När är hemleverans mer effektivt än leverans via utlämningsställe?

Kerrén, Thed January 2019 (has links)
In the literature on B2C logistics of e-commerce, the two main delivery methods - home delivery and delivery to collection-delivery points (CDPs) - have rarely been compared with respect to their environmental effects. This is the case despite a growing e-commerce and the fact that the logistic part of the transportation sector stands for a great amount of the pollution in urban areas. In this report, the two delivery methods have been compared to each other with respect to their environmental impacts through a custom-made network impact model, including simulation using vehicle routing problems (VRPs) and a cross-nested logit model. The results show that one delivery method's advantage over the other (only regarding emissions) is strongly dependent on the distance to the distribution center (DC), the customer density, the density of CDPs and the demographics of that area. Home deliveries proved to be more sensitive to the customer density factor and the distance to the DC than CDP deliveries. / I litteraturen om e-handelslogistik har de två huvudsakliga leveransmetoderna -- hemleverans och leverans till utlämningsställe (CDP) -- sällan jämförts med avseende på deras miljöeffekter. Detta trots en växande e-handel och faktumet att logistikdelen av transportsektorn står för en stor del av föroreningarna i städer. I denna rapport har de två leveransmetoderna jämförts med avseende på deras miljöpåverkan genom en skräddarsydd modell, som bygger dels på simulering med hjälp av ruttplaneringsproblem (VRP) och dels på en korsnästad logitmodell (CNL). Resultaten visar att vilken leveransmetod som presterar bäst (räknat utifrån lägst utsläpp), är starkt beroende av avståndet till distributionscentret (DC), kundtätheten, tätheten av utlämningsställen och områdets demografi. Hemleveranser visade sig vara mer känsliga för kundtätheten och avståndet till distributionscentret än leveranser via utlämningsställe.
372

Understanding consumers' ornamental plant preferences for disease-free and water conservation labels

Hartter, David L. 27 August 2012 (has links)
Product labeling is increasingly used as a tool to differentiate products with public and private benefits that cannot be readily evaluated by a consumer at the time of purchase. Our research investigates how a labeling program may be applied in the sale of ornamental plants to address two key issues; plant disease and irrigation water use. A choice modeling survey was utilized to estimate consumers' willingness to pay a premium for six ornamental plants with disease-free and/or water conservation certification labels. The results of the mixed logit models show consumers are willing to pay a premium for plants certified as disease-free and/or produced with water conservation practices. The results strongly suggest producers can recoup some of the costs of implementing water conservation measures such as water recycling and disease control measures amid regulatory and drought concerns. Our research also investigated consumers' preferences for multiple third party certifying authorities and whether preferences for the labels varied among consumers. The results showed ornamental plant consumers did not reveal a preference for a particular certifying authority. The results are mixed as to whether willingness to pay for the labels varies among respondents. We show willingness to pay does vary among respondents for three of the plant models indicating preference heterogeneity. / Master of Science
373

Analysis of Metropolitan Outmigration of Elderly Females In Canada: 1971-76

Cheung, Heidi Yin-Fan 07 January 1986 (has links)
<p> This paper analyzes the 1971-1976 outmigration pattern of the Canadian female elderly from the 23 Census Metropolitan Area's (CMA's). The migration is conceptualized as a three-level choice process and is represented by the logit model. The major findings are as follows: (1) Elderly females are substantially less migratory than young females but are slightly more mobile than elderly males. In addition,, the elderly females in the Western region tend to be more mobile than those in other regions. (2) Elderly females show less preference for the metro politan destinati ons than the young population; however, among the elderly, females have a stronger preference for metropolitan areas than males. (3) In general, the metropolita~d outmiS!'ants' destination choice pattern is less dispersed for the elderly than for the young. Among the older persons, female migrants have a larger dispersion than male migrants in most CMA's. (4) With respect to metropolitanward elderly migrants from the CMA's, the probability of choosing a particular destination is positively related to population size, brightness , and housing growth, and negatively related to the logarithm of di stance, cultural dissimilarity, coldness, and gross rent. (5)Environmental variables are more important than the housing variables in determining the destination choice pattern of the elderly mi grants. </p> / Thesis / Bachelor of Arts (BA)
374

Essays on Taxation, Marriage, and Labor Supply

Zhang, Yonghui 28 September 2015 (has links)
My dissertation consists of three essays on labor supply responses, along the extensive margin (participation into the labor force) and along the intensive margin (intensity of work on the job). The first two essays focus on the labor supply responsiveness of single women with children to taxation and welfare programs. The third essay investigates the effects of marriage, the wage rate, and the associated tax rate on men's labor supply. In the first essay, to avoid bias from the fact that labor supply outcomes are being driven by self-selection, I build a dynamic stochastic discrete choice model to investigate the long run effects of the earned income tax credit and welfare policies on single mothers' labor supply. Simulated method of moments is used to estimate parameters of this dynamic model, based on March CPS data files from 1964 to 2013. I compare the performance of the dynamic stochastic discrete choice model, a static model, and a reduced-form model. My analysis concludes that the dynamic stochastic discrete choice model captures the simultaneous impact of the state variables on the predicted employment decision. My study provides evidence of the long-run positive effect of public policy on low income families in a life-cycle setting. This essay also emphasizes the importance of education in increasing single mothers' labor supply. The second essay is designed to identify factors that help single mothers leave TANF within a short span of time. I find strong evidence for the importance of child support assistance to single mothers' success in exiting TANF with a job. I uncover evidence that work-related activities do not induce TANF participants to leave within a short span of time. My analysis also suggests that health issues significantly limit the ability of single mothers to exit TANF. In the third essay, the main research question is how marital status affects the elasticity of the labor supply of males with respect to wages and taxes, in a life-cycle setting. A dynamic panel data model, which extends the literature on dynamic labor supply, indicates that the elasticity of men's labor supply with respect to wages and taxes is affected by marital status. The empirical results using the Panel Study of Income Dynamics (PSID) data show that men who are continuously married to the same wife have a lower average Frisch elasticity than others. / Ph. D.
375

Learning From the Implementation of Residential Optional Time of Use Pricing in the U.S. Electricity Industry

Li, Xibao 25 March 2003 (has links)
No description available.
376

Essays on the temporal insensitivity, optimal bid design and generalized estimation m odels in the contingent valuation study

Kim, Soo-Il January 2004 (has links)
No description available.
377

Essays on applied spatial econometrics and housing economics

Kiefer, Hua 22 June 2007 (has links)
No description available.
378

Capacity Expansion of Electric Vehicle Charging Network: Model, Algorithms and A Case Study

Chen, Qianqian January 2019 (has links)
Governments in many counties are taking measures to promote electric vehicles. An important strategy is to build enough charging infrastructures so as to alleviate drivers’ range anxieties. To help the governments make plans about the public charging network, we propose a multi-stage stochastic integer programming model to determine the locations and capacities of charging facilities over finite planning horizons. We use the logit choice model to estimate drivers’ random choices towards different charging stations nearby. The objective of the model is to minimize the expected total cost of installing and operating the charging facilities. Two simple algorithms are designed to solve this model, an approximation algorithm and a heuristic algorithm. A branch-and-price algorithm is also designed for this model, and some implementation details and improvement methods are explained. We do some numerical experiments to test the efficiency of these algorithms. Each algorithm has advantages over the CPLEX MIP solver in terms of solution time or solution quality. A case study of Oakville is presented to demonstrate the process of designing an electric vehicle public charging network using this model in Canada. / Thesis / Master of Science (MSc)
379

Modeling land-cover change in the Amazon using historical pathways of land cover change and Markov chains. A case study of Rondõnia, Brazil

Becerra-Cordoba, Nancy 15 August 2008 (has links)
The present dissertation research has three purposes: the first one is to predict anthropogenic deforestation caused by small farmers firstly using only pathways of past land cover change and secondly using demographic, socioeconomic and land cover data at the farm level. The second purpose is to compare the explanatory and predictive capacity of both approaches at identifying areas at high risk of deforestation among small farms in Rondõnia, Brazil. The third purpose is to test the assumptions of stationary probabilities and homogeneous subjects, both commonly used assumptions in predictive stochastic models applied to small farmers' deforestation decisions. This study uses the following data: household surveys, maps, satellite images and their land cover classification at the pixel level, and pathways of past land cover change for each farm. These data are available for a panel sample of farms in three municipios in Rondõnia, Brazil (Alto Paraiso, Nova União, and Rolim de Moura) and cover a ten-year period of study (1992-2002). Pathways of past land cover change are graphic representations in the form of flow charts that depict Land Cover Change (LCC) in each farm during the ten-year period of study. Pathways were constructed using satellite images, survey data and maps, and a set of interviews performed on a sub-sample of 70 farms. A panel data analysis of the estimated empirical probabilities was conducted to test for subject and time effects using a Fixed Group Effects Model (FGEM), specifically the Least Square Dummy Variable (LSDV1) fixed effects technique. Finally, the two predictive modeling approaches are compared. The first modeling approach predicts future LCC using only past land cover change data in the form of empirical transitional probabilities of LCC obtained from pathways of past LCC. These empirical probabilities are used in a LSDV1 for fixed–group effects, a LSDV1 for fixed-time effects, and an Ordinary Least Square model (OLS) for the pooled sample. Results from these models are entered in a modified Markov chain model's matrix multiplication. The second modeling approach predicts future LCC using socio-demographic and economic survey variables at the household level. The survey data is used to perform a multinomial logit regression model to predict the LC class of each pixel. In order to compare the explanatory and predictive capacity of both modeling approaches, LCC predictions at the pixel level are summarized in terms of percentage of cells in which future LC was predicted correctly. Percentage of correct predicted land cover class is compared against actual pixel classification from satellite images. The presence of differences among farmers in the LSDV1-fixed group effect by farmer suggests that small farmers are not a homogeneous group in term of their probabilities of LCC and that further classification of farmers into homogeneous subgroups will depict better their LCC decisions. Changes in the total area of landholdings proved a stronger influence in farmer's LCC decisions in their main property (primary lot) when compared to changes in the area of the primary lot. Panel data analysis of the LCC empirical transition probabilities (LSDV1 fixed time effects model) does not find enough evidence to prefer the fixed time effects model when compared to a Ordinary Least Square (OLS) pooled version of the probabilities. When applying the results of the panel data analysis to a modified markov chain model the LSDV1-farmer model provided a slightly better accuracy (59.25% accuracy) than the LSDV1-time and the OLS-pooled models (57.54% and 57.18%, respectively). The main finding for policy and planning purposes is that owners type 1—with stable total landholdings over time—tend to preserve forest with a much higher probability (0.9033) than owner with subdividing or expanding properties (probs. of 0.0013 and 0.0030). The main implication for policy making and planning is to encourage primary forest preservation, given that the Markov chain analysis shows that primary forest changes into another land cover, it will never go back to this original land cover class. Policy and planning recommendations are provided to encourage owner type 1 to continue their pattern of high forest conservation rates. Some recommendations include: securing land titling, providing health care and alternative sources of income for the OT1's family members and elderly owners to remain in the lot. Future research is encouraged to explore spatial autocorrelation in the pixel's probabilities of land cover change, effects of local policies and macro-economic variables in the farmer's LCC decisions. / Ph. D.
380

Factores latentes de la desviación de presupuestos en proyectos de arquitectura. Un análisis empírico

Bustos Chocomeli, Óscar Hugo 31 March 2015 (has links)
Esta tesis pretende profundizar en el paradigma del sistema presupuestario de proyectos de arquitectura, centrando su atención no tanto en los efectos sino en las causas de la desviación de sus presupuestos. Así, se analizan los tránsitos históricos de la disciplina y el reciente panorama en el que toman fuerza nuevas metodologías de gestión aplicadas en el sector de la edificación como el Fuzzy o el Activity Based Costing (ABC). En el marco experimental se persigue modelizar el sistema complejo “Desviación de presupuestos” recurriendo a las herramientas estadísticas del Análisis Factorial de Componentes Principales y la Regresión Logística Multinomial; Desde la Literatura, se analizan las variables objetivos recurrentes, y se genera el modelo conceptual hipótesis del constructo. Apoyado en dicho constructo teórico, se desarrolla la técnica Delphi de expertos que sirve de base para la elaboración de un cuestionario a profesionales. Del análisis y tratamiento de sus datos, se extraen las correspondientes conclusiones del modelo. / Bustos Chocomeli, ÓH. (2015). Factores latentes de la desviación de presupuestos en proyectos de arquitectura. Un análisis empírico [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48558

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